Depends on what you consider playable and whether you want accurate fighters based on their real life performances. Hendricks and Penn arent viable online especially in ranked. Thats because both of them are still active fighters and they are currently pretty bad.
BJ hasnt won a fight in 8 years and has been dominated in 4 of his last 5 fights. Hendricks has lost 4 of his last 5 and has been dominated in most of his recent fights (His power and accuracy are good though).
If BJ would retire or if EA would create a classic version of BJ, he would absolutely be viable. If they made a prime version of Hendricks, he would absolutely be viable. But these are supposed to be the current versions of those fighters and their current versions arent that good right now.